Method for providing a substrate with a liner



April 29, 1969 w. R. HERRING METHOD FOR PROVIDING A SUBSTRATE WITH ALINER INVENTOR. WALTER R. HER/PING Sheet Original Filed April 8, 1963M/MJL ATTORNEY W. R. HERRING 7 April 29, 1969 METHOD FOR PROVIDING ASUBSTRATE WITH A LINER Sheet 2 Original Filed April 8, 1963 FIG.5

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INVENTOR. WALTER R. HER/PING ATTORNEY April 29, 1969 w. R HERRING METHODFOR PROVIDING A SUBSTRATE WITH A LINER Sheet Original Filed April 8,1963 FIG."

INVENTOR. WALTER R. HERE/N6 BY Sf Z ATTORNEY United States Patent 0"3,440,709 METHOD FOR PROVIDING A SUBSTRATE WITH A LINER Walter RaymondHerring, Unionville, Pa., assignor t0 Container Corporation of America,Wilmington, Del.,

a corporation of Delaware Original application Apr. 8, 1963, Ser. No.271,126, now

Patent No. 3,387,355, dated June 11, 1968. Divided and this applicationFeb. 7, 1968, Ser. No. 718,968

Int. Cl. B23p 11/02 US. Cl. 29-450 6 Claims This application is adivision of my copending application Ser. No. 271,126 filed Apr. 8,1963, now Patent No. 3,387,355, and entitled, Method and Apparatus forProviding a Substrate With a Liner.

This invention relates to a method of providing a substrate with aliner. In particular, the present invention is related to the mechanicaljoining of a flexible polymeric film, such as a thin sheet ofpolyethylene, onto rigid substrates such as sheet metal covers forcontainers and the like.

In general, the present invention is related to the art of packaging,but has applications in a wide variety of fields. Heretofore, rigid allplastic containers have been utilized for storing and transportingchemical, liquids, and granular materials which are of such a naturethat they could not be disposed within metal containers because of achemical or other reaction which would take place. While useful,economical and practical considerations prevent employment of suchcontainers as low cost ex pendable shipping containers, low costpractical containers of known construction are available and may be usedproviding certain improvements are made.

Relatively low cost, mass produced metal and/ or metalfiber containerscan be endowed with the desirable qualities afforded by such plasticswhen a lightweight, thin film barrier is employed on the inner surfaceof the container. Such composite containers feature an inner barrierfilm intimately disposed on the inner surface of the container and thenpossess the dual advantages of the plastic containers combined with thedesirable features of the metal and/or metal-fiber containers.

In combining a barrier film with a heretofore conventional metal and/ormetal-fiber container, certain practical problems arise. The presentinvention relates to apparatus and method for satisfactorily andefficiently solving a specific problem with respect to joining a barrierfilm t0 the cover for the container. It will be understood, however,that the method and apparatus of the present invention are notrestricted to the described instance of use, but can be employed in avariety of non-related applications where the method and apparatus canachieve the desired end result.

Metal and/or metal-fiber containers are generally provided with aremovable cover. The cover is generally fixed to the container body by aknown means and firmly held in place by a known clamping device, such asa locking retaining ring. In some instances, the cover device may bepermanently assembled to the container body at the time of manufacture.Thereafter, the access for filling or emptying is accomplished throughsuitable means such as threaded closures. The cover must have on itsinner surface a barrier film similar in properties and effects to theinner surfaces of the container so that the assembled container willpresent the required barrier film throughout its entire inner surfaces.

Where plain metal discs are employed as covers for containers, it is arelatively easy matter to provide a contoured sheet of plastic filmbarrier material. The plastic disc may be merely placed on the open endof the container, and then held in place when the metallic disc cover3,440,709 Patented Apr. 29, 1969 ice is seated and locked in position.To facilitate handling and to assure proper alignment, the plastic discmay further be afiixed by providing a known suitable adhesive betweenthe disc and the metal cover.

It is often desirable to provide openings in the cover to allowconventional filling and/or emptying operations to be effected withoutremoving the cover. Heretofore, it has been conventional to provide aflange on the cover around any such openings for receiving closuremembers of known construction. Such closure members are generally madeof plastic materials compatible with the container linings and are ofsuch construction that no metal components are exposed to the innersurface of the container. It is with respect to such a cover having aflange opening with which the present invention is particularly directedand adapted to be utilized.

It must be appreciated that where barrier films are employed, the filmsurface must be interrupted to provide access through the cover and thefilm barrier to the containers contents. If sections of barrier filmsare provided with apertures adapted to coincide with any apertures inthe cover, the resultant discontinuity of the barrier film would defeatthe purpose of the barrier film since that portion of the cover aroundthe aperture will be exposed to the contents of the container.

It is an object of the present invention to provide a novel method forjoining a barrier film to a rigid substrate.

It is another object of the present invention to provide a novel methodfor joining a barrier film of polymeric material to a rigid substratehaving a flanged opening.

It is another object of the present invention to provide a novel methodfor providing an uninterrupted barrier film on the inner surface of ametal cover for a container with said cover having a flanged opening.

It is another object of the present invention to provide a novel methodfor applying barrier films to rigid covers for containers in a mannerwhich is rapid, reliable, effective and economical.

It is another object of the present invention to provide a method forjoining polyethylene liners to metal container covers in a manner whichcan be utilized mechanically or manually.

It is still another object of the present invention to provide a methodfor joining a polyethylene barrier film to a metal container coverhaving a flanged opening in a manner which results in the entire innersurface of the cover having an uninterrupted barrier film.

Other objects will appear hereinafter.

For the purpose of illustrating the invention there is shown in thedrawings forms which are presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand instrumentalities shown.

FIG. 1 is a side elevation view of a typical embodiment of the apparatusused in the method of the present invention.

FIG. 2 is a sectional view taken along the lines 2-2 in FIG. 1.

FIG. 3 is a sectional view taken along the lines 3-3 in FIG. 2.

FIGS. 47 are diagrammatic illustrations of the steps involved inpracticing the method of the present invention with the apparatusillustrated in FIGS. 1-3.

FIG. 8 is a sectional view through a cover having a flanged opening anda barrier film juxtaposed thereto in accordance with the presentinvention, with the illustration being an enlarged detail view.

FIG. 9 is a perspective view of a component of the apparatus used in themethod of the present invention.

FIG. 10 is a longitudinal sectional view of the apparatus in accordancewith another embodiment.

FIG. 11 is a perspective view of the apparatus illustrated in FIG. 10,when in use.

Referring to the drawing in detail, wherein like numerals indicate likeelements, there is shown in FIG. 1 a side elevation view of oneembodiment of the apparatus of the present invention designatedgenerally as 10.

The apparatus may include a separate frame base 12 or may be mounted onsome conventional support such as a table or the like. An upright column14 is supported by the base 12. A support member 16 is adjustablysupported by the column 14 by means of an adjustable clamping or bracketdevice 18.

A cylinder 20 is supported in an upright disposition by the supportmember 16 in a conventional manner by use of brackets. The cylinder 20is provided with motive fluid coupling conduits 22 and 24 at oppositeends thereof. A piston rod 26 extends through an end wall of thecylinder 20 in a downward direction and is coupled to a piston (notshown) within the cylinder 20.

The lower end of the piston rod 26 is adjustably coupled to a connectorrod 26 on a trim tool 28. The trim tool 28 includes an annular housing29 which may be made from any poor conductor of heat such as athermosetting resin. A cutter body 30, made from a good heat conductorsuch as aluminum, is adjustably supported within the housing 29 andprovided with an annular cutting surface 32 in the form of a downwardlyprojecting boss.

The body need not be made from a good heat conductor unless it isdesired to provide the trim tool 28 with heaters. As illustrated, trimtool 28 is provided with heaters 34 and an adjustable thermostat 36.

An anvil having a cutting edge 42 on its upper surface is disposed belowthe trim tool 28. The cutting edge 42 is of a configurationcorresponding to the configuration of the cutting surface 32. Anvil 40is supported at the upper end of a cylindrical anvil carrier 44. It willbe noted that the cutting edge 42 is disposed radially inwardly from theouter peripheral surface of the carrier 44.

The carrier 44 terminates at its lower end, on its inner surface, in anaxially directed surface which merges into a curved surface 46. An anvilsupport 48 is provided within the carrier 44 immediately below the anvil40. A plurality, such as two, four or six, of guide rods 52 areprovided. Guide rods 52 support the anvil support 48 in a fixeddisposition above a base 50.

The base is provided with an axially extending bore 54 which is in linewith an axially extending bore 56 in the anvil support 48. A rod 55extends through the bores 54 and 56 and is guided thereby forreciprocation in an upright direction. The base 50 terminates at itsupper outer peripheral portion in an axially extending surface merginginto a curved surface 58. Hence, it will be noted that the lower endportion of the barrier 44 and the upper end portion of the base 50 areprovided with spaced parallel axially extending surfaces merging intocurved surfaces which terminate at the periphery of the carrier 44 andbase 50.

A carriage 60 is connected to the rod 55 and guided by the rods 52. Aplurality of fingers 62 are carried by the carriage 60. Preferably, thefingers 62 are integral at one end with an annular band 63. The band 63is clamped to the outer periphery of the carriage 60 in a peripheralnotch on said carriage. Hence, as said carriage reciprocates, saidfingers reciprocate therewith.

The fingers 62 may be referred to hereinafter as flexible formingmembers. The fingers 62 and band 63 are capable of being manufactured ina wide variety of processes. One method of making such structure is tostart with a small cylinder and provide saw cuts from one end therebyforming the fingers 62. The fingers 62 and band 63 are preferably formedfrom a flexible material having a thickness of about 0.1 inch. It hasbeen found that the fingers 62 function very efficiently when made from-Teflon. However, other materials such as polyethylene may be utilized ifdesired.

It will be noted that the fingers 62 are of sufficient length so as toextend through the axially extending annular passage and curved passagebetween the lower end portion of the carrier 44 and the upper endportion of the base 50. The purpose of the fingers 62 will be made clearhereinafter. The base 50 is preferably surrounded by a resilient pad 64of foam rubber or the like. The base 50 and pad 64 are mounted on ahorizontal platform 66 supported above the base 12 by support member 68.

A cylinder 70 is disposed in an upright disposition and supported by thesupport member 68. Cylinder 70 is provided with motive fluid couplingconduits 72 and 74 at opposite ends thereof. A piston rod 76 extendsthrough the upper end wall of the cylinder 70. The lower end of thepiston rod 76 is coupled to a piston (not shown) within the cylinder 70.The upper end of piston rod 76 is coupled to rod 55 by means of anadjustable bracket 78.

The apparatus and method of the present invention is particularlyadapted for joining a barrier film 86 to a rigid substrate such as themetal cover 80 for a container. Cover 80 may be of a size up to two feetin diameter or more and may include a peripheral downwardly extendingflange, a radially inwardly disposed annular zigzag bend 82 and anupwardly extending flange 84 surrounding an opening therein. Flange 84,per se, is of known construction and widely employed with known closuredevices of excellet characteristics. Flange 84 is formed in a manner sothat its upper end is a curved surface corresponding to approximatelydegrees of a circle.

The barrier film 86 is preferably a film of polyethylene or the likehaving a thickness of about .002.l inch. The barrier film 86 has aperipheral contour corresponding to the contour and configuration of thecover 80. The periphery of the barrier film 86 overlaps both sides ofthe peripheral depending flange on the cover 80.

The barrier film 86 may be produced by means of a variety of processes.Preferably, the barrier film 86 is formed and shaped so that itcorresponds to the shape of the cover and is provided with at least oneintegral boss 88. The axially extending wall of the boss 88 and the endwall of the boss 88 are of substantially the same thickness with thelength of the axially extending wall being slightly greater than theaxial length of the flange 84. It will be noted that the end wall of theboss 88 lies in a substantial horizontal plane parallel to the plane ofthe major portion of the barrier film 86. Preferably, the boss 88 isproduced by a vacuum forming process.

The boss 88 has a surface area which is slightly less than the surfacearea of the flange 84 which is to be covered. The boss 88 is designedand arranged so that when various reverse folds are made, the materialwill conform to a new shape without wrinkling, creasing or puckering. Ithas been found that relatively thin films of the polymeric materialsutilized for the barrier film 86 possess inherent elasticity which canexceed an elongation value of sixhundred percent.

The operation of the apparatus 10 and the method of the presentinvention is as follows:

A barrier film 86 will be produced as described above and juxtaposed tothe substrate, such as the cover 80, in a manner so that the boss 88extends through the aperture defined by the flange 84. The trim tool 28will be spaced from the anvil 40 as illustrated in FIGURE 1 so that thebarrier film and substrate may be held therebetween.

The operation of the apparatus 10 and the method of the presentinvention are diagrammatically illustrated in FIGURES 4-7. The substrateand barrier film will be juxtaposed to one another and held in thedisposition as illustrated in FIGURE 4. Thereafter, by introducingmotive fluid into cylinder 20, the trim tool 28 will be reciprocateddownwardly to the position illustrated in FIG- URE 5. Since the cuttingedge 42 of the anvil 40 is juxtaposed to the inner surface of the endwall of the boss 88, the resultant application of heat and/ or pressureby the cutting surface 32 against the cutting edge 42 with the end wallof the boss 88 therebetween results in the cutting of a disc 90 from theend wall of boss 88, as illustrated in FIGURE 6. Thereafter, the trimtool 28 will be reciprocated to its normal disposition.

As soon as the disc 90 has been cut from the end wall of the boss 88,the substrate and barrier film may descend to a position wherein theyare supported by the platform 66 and pad 64. While the barrier filmdescends, the terminal edge 94 is constricted around the carrier 44since it has a smaller diameter. While the outer periphery of the cover80 need not be supported, the portion of the cover 80 around the flange84 will be resiliently supported.

It will be noted that the cutting of the disc 90 converts the boss 88into an annular flange 92 having a free terminal edge 94. Further, itwill be noted that the resultant disposition of the cover 82- is suchthat the free end portion of the flange 92 is now juxtaposed to theterminal end of the finger 62.

Motor fluid is now introduced into the cylinder 70 to reciprocate rod 55downwardly as illustrated in FIGURE 7. Downward reciprocation of rod 55results in downward reciprocation of the carriage 60 and the finger 62.The axially extending passageway which merges into a curved outwardlyextending passageway between the lower end of'the carrier 44 and theupper end of the base 50 causes the finger 62 to move outwardly asillustrated in FIGURE 7. Such outward movement of the terminal portionof the fingers 62 effect a stretching out of the flange 92 to cause thesame to embrace the outer periphery of the boss 88 as illustrated indetail in FIGURE 8. The stretching force is exerted on portions of theflange 92 which are juxtaposed to a varying contour on the flange 84thereby enabling a pronounced stretching out of flange 92 and cause theflange 92 to conform to the general contour of the flange 84. The flange92 is stretched in all radial planes at the same time. Radial planes arenecessary to permit the stretching effect to be exerted on large areasof the barrier film to eliminate rupture of the film while achieving ahigh degree of even tension. The even expanding force exerted on theflange 92 causes it to dilate until it has somewhat exceeded thediameter of the flange 84. Thinning out of the film is kept to a lowvalue since the stretching is imposed over the vertical and into theflat plane base area and the needed material is drawn from a relativelylarge surface area of the barrier film 86.

When the dilating, stretching and drawing force is applied outwardly andevenly at or just below the rim area of the flange 84, the walls of theplastic flange 92 will be drawn firmly and snugly over the profile ofthe flange 84. Further expanding of the flange 92 outwardly anddownwardly advances the free edge 94 thereof to a point where it is of adiameter substantially greater than the diameter of the flange 84.Tensional forces are now acting on all of the flange 92 so that itextends downwardly to the flat planar area of the cover 80.

The advance of the forming members 62 for their full stroke causes theleading edge portions of said forming members to advance through anarcuate path. This upward tilting of the leading edge portions permitsthe stretched and tensioned plastic terminal edge 94 to escape.Simultaneously, the inner faces of the forming fingers 62 are pressed inintimate contact with the area of the barrier film which has been drawnup and over the flange 84. Even after the terminal edge 94 has snappedoff the leading edges of the fingers 62, the remainder of the flange 92is held firmly in contoured juxtaposition with respect to the flange '84so that there is no loss of tension or recoil of the plastic materialduring the momentary transition period when the terminal edge 94 escapesfrom the fingers 62.

When the barrier film is thin such as a film having a thickness of .010inch, the pad 64 resiliently supports the portion of the cover aroundthe flange '84. The compressive force of the stroking of the fingers 62compresses the pad 64 (compare thickness of pad 64 in FIGURES- 6 and 7)and creates tension between the pad 64 and the juxtaposed portion of thebarrier film 86. This enables the thusly attained forming of the flange92 to be retained and prevents recovery of the material of the barrierfilm 86. If the barrier film 86 has a thickness such as .030 inch, thepad 64 may be omitted. When the barrier film has a thickness ofapproximately .010 inch, the leading edge on the fingers 62 arepreferably provided with a bead to minimize the likelihood of tearingthe film.

Thereafter, the rod 55 will be reciprocated upwardly to remove theforces of the finger 62 tending to expand the film thereby enabling theelastic tension of the flange 92 to return as far as possible to itsoriginal diameter. Since the material of the flange 92 has not beenstretched beyond its elastic limit, it will constrict itself around theouter profile of the flange 84 and be snugly retained therearound withsome tension in its new configuration as illustrated in FIGURE 8.

The completed assembly now features a rigid substrate provided on itsinner surface with an uninterrupted barrier film. The barrier film isnow joined to the substrate by the flange 92 and its cooperation withthe flange 84. Thereafter, the composite cover may be moved upwardlyuntil it is clear of the cutting edge 42. The disc 90 will havepreviously been removed. Thereafter, the process may be repeated. Itwill be noted that while the plastic material of the flange 92 has beencaused to conform to the contour of the flange 84, the fingers 62 do notlikewise follow the contour of the flange 84.

In FIGURES l0 and 11, there is illustrated another embodiment of theapparatus of the present invention designated generally as 100. Theapparatus is particularly adapted for manual operation. Apparatus 100performs a useful function in that it enables the barrier film to bereplaced in the field when such film is accidentally torn or otherwiseconsidered unacceptable. In view of the close similarity of theapparatus 10 and the apparatus 100, corresponding elements of apparatus10 are provided with corresponding primed numerals.

The apparatus 100 includes a base 102 having a central axial bore 104and a radially outwardly directed peripheral bead 103. A bushing 106 isreciprocally guided by the bore 104 and coupled at its upper end to asubstantially horizontally disposed carriage 108 by means of a bolt 110.

The carriage 108 is provided with an upstanding tubular handle 112. Ahandle grip 114 is telescopically disposed over the handle 112 andprovided with finger grip portions 116. The bushing 106 and the carriage108 are biased upwardly against a limit stop effected by setscrew 118 bymeans of a spring 117. Spring 117 is disposed within the bore 104 andextends between a radially inwardly directed flange 119 and the lowersurface of the bushing 106.

The carriage 108 is provided with a peripheral notch 126 within which isdisposed the uninterrupted band 63' having depending discrete fingers62'. The band 63' is retained in the notch 126 by means of strap 122Which may have its tension adjusted by means of clamp 124. A resilientconstrictor 120 surrounds the fingers 62' at a point aproximating theupper end of the base 102. It will be noted that the base 102 isprovided with an outer peripheral surface which is axially directed andwhich merges into the curved surface 58'.

In operation, the apparatus 100 is substantially identical with thatdescribed above except as will be made clear hereinafter. The substrateor cover 80' will have a barrier film 86' juxtaposed thereto with a bossextending through the aperture defined by the flange 84' on thesubstrate or cover 80'. Manually, the boss end wall will be cut toproduce the flange 92'. Thereafter, the base 102 will be insertedthrough the hole in the end wall of the boss so as to effect thedisposition illustrated in FIGURE 10. By manually applying pressure tothe carriage 108 by way of the handle 112, the fingers 62' may be causedto be reciprocated to eflect a stretching of the flange 92' in the samemanner as described above.

Each of the embodiments of the present invention are rapid, efficient,reliable and facilitate the economical joining of a barrier film to arigid substrate.

The stretching of the barrier film flange and subsequent constrictionaround the substrate flange is a type of snap fitting operation. It willbe noted that the free end of the barrier film flange has a diameterwhich is less than and below the largest diameter of the substrateflange, see FIGURE 8. As will be obvious from the above, the joiningoperation is eflected without the use of adhesive.

For purposes of illustration, the axial length of the flange 84 may beabout A of an inch whereas the axial length of the boss 88 would beabout of an inch when used therewith. From these figures, one mayappreciate the shallowness of the draw when forming the boss 88 and therelative dimensions of axial lengths of the flanges on which the presentinvention has performed successfully.

While the fingers 62 or 62 are preferably made of Teflon, they may bemade of polyethylene, polypropylene, spring metal, etc. The barrier film86 may be any of a wide variety of resilient polymeric materials capableof acting as an elastometer.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, other thanto the foregoing specification as indicating the scope of the invention.

It is claimed:

1. A method of joining a barrier film liner of an elastomeric materialto a substrate comprising the steps of jutaposing a barrier film linerto the substrate in a manner so that a flange on the liner extendsthrough a flange on the substrate, with the barrier film flange being ofan axial length so that it extends entirely through the flange of thesubstrate, extending a forming member through said flanges, elasticallydilating the barrier film flange radially outwardly along substantiallyits entire circumference and over the substrate flange by means of saidforming member, and then elastically constricting the free edge portionof the barrier film flange around the outer periphery of the substrateflange.

2. A method of joining a liner of polymeric material to a rigidsubstrate comprising the steps of juxtaposing the liner to the substrateso that a boss on the liner ex tends entirely through a flange on thesubstrate, cutting a disc out of the end face of the boss to form aflange on the liner, elastically stretching substantially the entirecircumference of the liner flange around the outer periphery of thesubstrate flange, and elastically constricting the free edge portion ofthe liner flange around the substrate flange.

3. A method in accordance with claim 2 wherein the stretching step isaccomplished by moving flexible forming members in an axial directionwith respect to said flanges and causing terminal portions of theflexible forming members to flex substantially radially outwardlythrough an arcuate path to engage the liner flange and cause the same tobe stretched around the substrate flange.

4. A method comprising the steps of providing a rigid substrate having aflange surrounding an aperture, providing a liner of polyethylene havingsubstantially the same configuration as the substrate and a boss in amanner whereby the boss has an annular side wall and an end face ofsubstantially the same thickness, juxtaposing the liner to the substratein a manner so that the boss extends through the substrate flange,cutting a disc out of the end face of the boss thereby converting theboss into a flange having an axial length at least as long as the axiallength of the substrate flange, elastically stretching the liner flangeat substantially its entire circumference until the liner flange extendsaround the substrate flange, and elastically constricting the free edgeportion of the liner flange around the outer periphery of the substrateflange so that the diameter at the free edge of the liner flange is lessthan and below the greatest diameter of said substrate flange.

5. A method of joining an elastomeric liner to a rigid metal covercomprising the steps of providing a rigid metal cover with a flangesurrounding an aperture in the cover, juxtaposing a liner to the coverin a manner so that a flange on the liner extends through the coveraperture, extending a forming member through the liner flange,elastically dilating the liner flange radially outwardly alongsubstantially its entire circumference by means of elements of saidforming member, said dilating step being accomplished so that the linerflange elastically stretches over and embraces the outer periphery ofthe substrate flange, elastically constricting the free edge portion ofthe liner flange around the outer periphery of the substrate flange sothat the diameter at the free edge of the liner flange is less than andbelow the greatest diameter of said substrate flange, and then removingsaid forming member.

6. A method of joining an elastomeric barrier film to a rigid substratecomprising the steps of juxtaposing the liner to the substrate so that aboss on the liner extends through a flange on the substrate, cutting adisc in the end face of the boss thereby forming a liner flange, andthen causing the liner flange to elastically snap-over the substrateflange in a manner so that the entire circumference of the liner flangestretches over the substrate flange simultaneously and constrictstherearound.

References Cited UNITED STATES PATENTS Dutton 29-450 CHARLIE T. MOON,Primary Examiner.

1. A METHOD OF JOINING A BARRIER FILM LINER OA AN ELASTOMERIC MATERIALTO A SUBSTRATE COMPRISING THE STEPS OF JUTAPOSING A BARRIER FILM LINERTO THE SUBSTRATE IN A MANNER SO THAT A FLANGE ON THE LINER EXTENDSTHROUGH A FLANGE ON THE SUBSTRATE, WITH THE BARRIER FILM FLANGE BEING OFAN AXIAL LENGTH SO THAT IT EXTENDS ENTIRELY THROUGH THE FLANGE OF THESUBSTRATE, EXTENDING A FORMING MEMBER THROUGH SAID FLANGES, ELASTICALLYDILATING THE BARRIER FILM FLANGE RADIALLY OUTWARDLY ALONG SUBSTANTIALLYITS ENTIRE CIRCUMFERENCE AND OVER THE SUBSTRATE FLANGE BY MEANS OF SAIDFORMING MEMBER, AND THEN ELASTICALLY CONSTRICTING THE FREE EDGE PORTIONOF THE BARRIER FILM FLANGE AROUND THE OUTER PERIPHERY OF THE SUBSTRATEFLANGE.